Date of Graduation
Statler College of Engineering and Mineral Resources
Civil and Environmental Engineering
Hema J Siriwardane
Atmospheric levels of carbon dioxide (CO2) have increased at a rate of about 1 to 2 parts per million (ppm) per year to its current level of approximately 388 ppm. Mitigation efforts are being deployed around the world in all possible ways to combat these accelerating levels of carbon dioxide. The study presented in this dissertation deals with the ground response caused by geologic sequestration of carbon dioxide. The ground response can be used as a tool for long-term monitoring of carbon storage in geological formations.;Unmineable coal seams have been identified as promising reservoirs for large-scale sequestration of carbon dioxide. A sequestration field site located in West Virginia and in the northern Appalachian basin has been used in this study. The field project is intended for geologic sequestration of carbon dioxide in a deep unmineable coal seam. The objective of the current study is to monitor any field-scale deformations resulting from the injection of carbon dioxide into a coal seam. Thirty six high-precision tiltmeters and two GPS receivers (absolute and remote) have been installed at the site to monitor surface deformations during the injection of CO2. Moreover, a multi-layered, three-dimensional, single-phase, coupled flow-deformation finite element model has been developed to investigate surface deformations during the injection. The model incorporates the topographical challenges and field-specific details. A finite difference based reservoir modeling approach was used to investigate the multi-phase fluid flow behavior in the coal seam by considering sorption/desorption properties and coal swelling/shrinkage. The results from multi-phase reservoir modeling were integrated in the finite element based geomechanical models. Tiltmeter measurements show the extent of deformations at the field site. The comparison of measurements and modeling results helps in calibrating numerical models that can be used to study reservoir response during large-scale injection of carbon dioxide. Results obtained from this study are useful in understanding the migration of fluid and pressure changes in the reservoir that helps in developing monitoring technologies.
Gondle, Raj Kumar, "Numerical Modeling and Field Monitoring of Overburden Response during Geologic Sequestration" (2010). Graduate Theses, Dissertations, and Problem Reports. 4598.